HTMLForm: Avoid usage of non-standard 'flags' parameter of String#replace

Chrome (and most other browser) don't support the non-standard 'flags'
argument to String#replace (implemented by Mozilla Firefox). Instead pass
a RegExp object with those flags.

Bug: 68050
Change-Id: Ia463002e708975eed1a5c3657f2e1a4d6b4e74de

resources/Resources.php

@@ -862,6 +862,9 @@ return array(
 	),
 	'mediawiki.htmlform' => array(
 		'scripts' => 'resources/src/mediawiki/mediawiki.htmlform.js',
+		'dependencies' => array(
+			'jquery.mwExtension',
+		),
 		'messages' => array( 'htmlform-chosen-placeholder' ),
 	),
 	'mediawiki.icon' => array(

resources/src/mediawiki/mediawiki.htmlform.js

@@ -363,7 +363,8 @@
 			$ul = $( this ).prev( 'ul.mw-htmlform-cloner-ul' );
 
 			html = $ul.data( 'template' ).replace(
-				$ul.data( 'uniqueId' ), 'clone' + ( ++cloneCounter ), 'g'
+				new RegExp( $.escapeRE( $ul.data( 'uniqueId' ) ), 'g' ),
+				'clone' + ( ++cloneCounter )
 			);
 
 			$li = $( '<li>' )